n. [ L. sestertius (sc. nummus), fr. sestertius two and a half; semis half + tertius third: cf. F. sesterce. ] (Rom. Antiq.) A Roman coin or denomination of money, in value the fourth part of a denarius, and originally containing two asses and a half, afterward four asses, -- equal to about two pence sterling, or four cents. [ 1913 Webster ]

☞ The sestertium was equivalent to one thousand sesterces, equal to £8 17s 1d. sterling, or about $43 (in 1900), before the reign of Augustus. After his reign its value was about £7 16s. 3d. sterling. The sesterce was originally coined only in silver, but later both in silver and brass. [ 1913 Webster ]